Power plant



y 1933- M. J. FINNEGAN ET AL 56 POWER PLANT Filed NOV. 13, 1936INVENTORS. Marf/h J. F/hneycm 8 Howard 506/ RNEY.

Patented May 31, 1938 UNITED STATES PATENT OFFICE,

POWER PLANT Application November 13, 1936, Serial No. 110,764

10 Claims.

invention relates to power plants and particularly to a power plantinvolving the provision of two or more distinct prime movers adapted forselective application to a single mechanism to be driven, whereby thepower for operating such mechanism to be driven may be taken from oneor'both of a pair of internal combustion engines, at the selection of anoperator, or in accordance with the density of the atmosphere from whichthe prime movers happen to be drawing the air for combustion of the fuelcharge.

When the invention is applied to a pair of engines carried by anaircraft, it will produce au tomatic cutting in and out of the second ofthe two engines, in accordance with variations in the altitude attainedby the craft.

Anobject of the invention is to provide, in a system of the foregoingcharacter, novel -means for controlling the successive starting of thetwo engines to be successively applied to the mechanism to be driven, aswell as the successive coupling operations themselves.

A further object of the invention is to provide in a system of theforegoing character a single source of energy to ignite the fuel chargeof either of the engines together with novel unitary control meanswhereby the ignition is automatically caused to occur in properly timedrelationship in each Ofthe'engines to which the driven mechanism iscoupled, and preferably as an incidental operation to the act of socoupling the successively energized engines thereto.

Other objects and features of the invention reside in the, specificconstruction and relationships of ,the elements and sub-combinationsentering into the complete system as will become apparent upon analysisof the following specification when considered in its relation to theaccompanying drawing illustrating one embodiment of the invention.

It is to be expressly understood, however, that 'the drawing is for thepurpose of illustration only, and is not designed as a definition of thelimits of the invention, reference being had to the ap-' pended claimsfor this purpose.

In the drawing:-

Fig. 1 is a schematic representation of the invention applied to a powerplant including a pair of successively energizable internal combustionengines and a single combination of elements to be driven therefrom;

Fig. 2 is a view in elevation of the altitude controlled switch; 7 andFigs. 3 and 4 are transverse views alonglines 3-3 and 4-4, respectively,in Fig. 2.

Referringfirst to Fig. l, the two internal combustion engines arerepresented therein at 5 and 6, and each is shown as'provided with anignition current distributor and a starting motor, the distributorsbeing shown at "I and 8 and starting motors at 9 and in for the engines5 and 6 respectively. interposed between" the two engines is a gear l4rotatable with a shaft l5 projecting from opposite sides thereof and.adapted to be driven by either of the clutch mechanisms l2 and i3, andin turn adapted to transmit rotation to a plurality of currentgenerating units or other accessories to be driven through interveninggear trains as indicated at l8 and I9. Included among these generatingunits (indicated by the reference characters 2|, 22, 23 and 24) is amagneto 24 constituting a source of ignition current to be distributedthrough one or both the distributors 'l and 3 in accordance with theconditions hereinafter more fully explained. The selection may occur'manually, or automatically in response to closure of the proper switchor combination of switches 30, 3|, and 32. When the switch 3i is movedin an upward (closing) direction, current is caused to fiow from thebattery 33 through the contacts 34 and 35 of the switch 3! to causeenergization of the electromagnetic devices 43, 44 and ill, the latterbeing the electric motor for starting the engine 6 as heretoforeindicated. Closure of the switch 30 or 32 (with switch 3| remainingclosed) would cause current to flow from the source 33 through theswitches 3i and 30 (or 32) in series, to energize the correspondingelectromagnetic devices 36, 3! and 9 associated with the engine 5. Theelectromagnetic devices 36 and 43 are shown as solenoidscontrolling theoperation of the clutch mechanisms l2 and I3, respectively, through theagency of shiftermechanisms 8| and 32 operatively connected to the endsof the solenoid plungers 41 and 48 respectively. In order to delay theoperation of the clutch mechanisms for a brief interval sumcient topermit the engine to acquire some speed, there is preferably interposedin the circuits of the solenoids 36 and 43 resistor units as indicatedat 5| and 52,\ respectively,' whereby solenoids 36 and 43 do not becomefully magnetized as readily as do the solenoids 3'! and 44, the latterbeing in direct shunt relationship to the windings of the motors 9 andI0 respectively and hence operative to close the switch 53 or 54, as thecase may be, promptly in response to flow of current thereto, thusassuring that theassociated engine willbe provided with ignition currentas soon as the crankshaft begins to turn under the influence of theenergization of the starter motor 9 or H]. Upon restoration of theswitch 3| to its normal position consequent deenergization of solenoids36 and 37, as well as 43 and 44, will likewise cause the return of thesolenoid plungers and associated mechanism to their original positionsdue to the action of the conventional normalizing springs (not shown)thereupon.

As soon as the engine develops suflicient power so that its crankshaftruns in excess of the speed of the starting gear the latter may bethrown to the inoperative position by the well-known overrunning action,assuming the use of some such starting mechanism as that known as theBendix drive; and by using a. centrifugal switch such as is indicated inFig. 2 of the Ertz Patent No. 1,940,- 712, the circuit to the electricmotor may be interrupted by the action of such speed responsive switch(indicated diagrammatically at 61 for the motor 9 and at 62 for themotor iii), the setting of these speed responsive switches being suchthat they are normally closed and moved to the open position only whenthe engine crankshaft acquires a speed approximately corresponding toits normal running speed. It will be noted that the branch' circuit tothe motor is the only one interrupted in this fashion, the othercircuits controlled by the switch 3| remaining closed so long as it isdesired to maintain the driven units 2| to 24 in operation. The clutchl2and the following is also true of clutch i3is preferably of acharacter which functions normally as a positive, non-slipping clutchbut initially as a slipping or friction clutch adapted to permit gradualpicking up of the load; the elements constituting the normal path oftorque transmission being a pair of gears or jaw clutch elements such asthe jaw clutch elements. designated by reference characters l9 and II inthe drawings of Patent No. 1,991,112 granted February 12, 1935 to RomeoM. Nardone. Such clutch elements have their meshable teeth so disposedin relation to the driving and driven shafts that driving engagement ofthe clutch is possible only when the said driving and driven shafts arein predetermined relative angular positions, thus assuring maintenanceof proper timing relationship between the engine crank-shaft and therotor of the magneto 24, to the end that the igniting spark shall alwaysoccur at the predetermined piston positions.

. capacity. During such ascent aneroid 9i (Figs. 2

and 3) will have been operative to swing sector 92 upward and rotatepinion 93 in a counterclockwise direction, thus permitting spring 94 torotate disc 95 to the extent of movement of the pin 96 (moving withpinion 93) in slot 91 of disc 95. Moving with disc 95 is a magnet 98designed to exert a magnetic attraction upon magnet 99 when movedsufficiently close thereto; whereupon contact arm 100, with which magnet99 is integrated, will be swung sharply in the clock-wise direction, asviewed in Fig. 4, to cause closure of contact llll upon contact I02,constituting the switch 390i Fig. 1. A stop 13 limits movement of armI00 as the craft descends.

What is claimed is:-

1. The combination with a plurality of internal' combustion engines,each having an ignition current distributor and starting motorassociated therewith, of an ignition current supply device common tosaid engines, means for causing the starting of one of said engines, andby the some action electrically connecting said ignition current supplydevice to the distributor of the engine to be started, said meanscomprising electrical conductors controlling energization of both thestarting motor and the distributor for each engine, and pressureresponsive means for controlling current fiow to one of said startingmotors and distributors, but not to the other.

2. The combination with a plurality of internal combustion engines, eachhaving an ignition current distributor and starting motor associatedtherewith, of an ignition current supply device common to said engines,means for causing the starting of one of said engines, and. by the sameaction electrically connecting said ignition current supply device tothe distributor of the engine to be started, said means comprisingelectrical conductors controlling energization of both the startingmotor and the distributor for each engine, electromagnetic means forcausing the coupling of each engineto said ignition current supplydevice, to rotate the latter and thereby cause it to generate ignitioncurrent, and means in circuit with said electrical conductors forenergizing said electromagnetic means.

3. The combination with a plurality of internal combustion engines, eachhaving an ignition current distributor and starting motor associatedtherewith, of an ignition current supply device common to said engines,means for causing the starting of one of said engines, and by the sameaction electrically connecting said ignition current supply device tothe distributor or the engine to be started, said means comprisingelectrical conductors controlling energization of both the startingmotor'and the distributor for each engine, and speed responsive meansfor interrupting the current flow to the starting motor.

4. The combinationwith a plurality of internal combustion engines, eachhaving an ignition current distributor and starting motor associatedtherewith, of an ignition current supply device common to said engines,means for causing the starting of one of said engines, and by the sameaction electrically connecting said ignition current supply device tothe distributor of the engine to be started, said means comprisingelectrical conductors controlling energization of both the startingmotor and the distributor for each engine, electromagnetic means forcausing the coupling of each engine to said ignition current supplydevice, to rotate the latter and thereby cause it to generate ignitioncurrent, and means in circuit with said electrical conductors forenergizing said electromagnetic means, said coupling v means includingclutch elements meshable only when the crankshaft is in a predeterminedangular position with respect to'said ignition current supply means.

5. The combination with a plurality of internal combustion engines, eachhaving a starting motor associated therewith, of means comprisingelectrical conductors for controlling energization of said startingmotors, and pressure responsive means for controlling current flow toone of said starting motors but not to the other.

6. The combination with a-plurality of internal combustion engines. eachhaving an ignition current distributor associated therewith, of anignition current supply device common to said engines, means forelectrically connecting said ignition current supply device to saiddistributors said means comprising electrical conductors for controllingenergization of the distributors, and pressure responsive means forcontrolling current flow to one of said-distributors but not to theother.

'7. The combination with a plurality of internal combustion engines,each having an ignition current distributor and starting motorassociated therewith, of an ignition current supply device common tosaid engines, means for causing the starting of a selected one of saidengines, and by the same action electrically connecting said ignitioncurrent supply device to the distributor of the selected engine, saidmeans comprising electrical conductors controlling energization of boththe starting motor and the distributor for each engine, and aneroidactuated means for controlling current flow to one of said startingmotors and distributors, but not to the other.

8. The combination with a plurality of internal combustion engines, eachhaving a starting motor associated therewith, of means comprisingelectrical conductors for controlling energization of said startingmotors, and aneroid actuated means for controlling current flow to oneof said starting motors but not to the other.

9. The combination with a plurality of internal combustion engines, eachhaving an ignition current distributor associated therewith, of anignition current supply device common to said engines, means forelectrically connecting said ignition current supply device to saiddistributors said means comprising electrical conductors for controllingenergization of the distributors, and aneroid actuated means forcontrolling current flow to one of said distributorsbut not to the.

other.

10. The combination with a plurality of internal combustion engines,each having a starting motor associated therewith, of means comprisingenergy conductors for controlling energization of said starting motors,and aneroid actuated means for controlling energy flow through one ofsaid conductors but not the other.

MARTIN J. FINNEGAN. HOWARD BAER.

